Related Experiment Video
Updated: Jan 19, 2026
Deciphering the Molecular Mechanism and Function of Pore-Forming Toxins Using Leishmania major
Published on: October 28, 2022
Characteristics of "Tip-DCs and MDSCs" and Their Potential Role in Leishmaniasis
Maximilian Schmid1, Anja K Wege, Uwe Ritter
1Institute of Immunology, University of Regensburg Regensburg, Germany.
Insights
Dendritic cells (DCs) and myeloid-derived suppressor cells (MDSCs) play key roles in immunity. This review questions if "Tip-DCs" and "MDSCs" are distinct subsets or transient myeloid cell stages.
Area of Science:
- Immunology
- Cell Biology
- Pathogen Research
Background:
- Dendritic cells (DCs) are crucial leukocytes in innate and adaptive immunity, particularly against intracellular pathogens like Leishmania major.
- Classifying myeloid cell types is challenging due to overlapping marker expression, necessitating careful interpretation for subtyping.
- The roles of TNF and nitric oxide-releasing DCs (Tip-DCs) and myeloid-derived suppressor cells (MDSCs) in infectious diseases require further investigation.
Purpose of the Study:
- To review the impact of Tip-DCs and MDSCs in experimental leishmaniasis.
- To discuss the classification challenges of myeloid cell subsets based on marker expression.
- To propose that Tip-DCs and MDSCs may represent transient myeloid cell maturation stages rather than distinct subsets.
Main Methods:
- Literature review and critical analysis of existing research on myeloid cell subsets in infectious diseases.
- Examination of molecular markers used for myeloid cell identification and subtyping.
- Discussion of the potential transient nature of myeloid cell populations like Tip-DCs and MDSCs.
Main Results:
- Overlapping marker expression complicates precise myeloid cell denomination and subtyping.
- Tip-DCs and MDSCs are implicated in the immune response to Leishmania major.
- Evidence suggests Tip-DCs and MDSCs might be transient myeloid cell states influenced by their environment.
Conclusions:
- The precise classification of myeloid cell subsets like Tip-DCs and MDSCs remains challenging.
- These cell types may not be classical subsets but rather represent dynamic maturation stages of myeloid cells.
- Further research is needed to elucidate the transient versus distinct subset nature of these myeloid cells in infectious contexts.
Abstract:
Since the first description of dendritic cells (DCs) by Steinman and Cohn (1973), the myeloid lineage of leukocytes was investigated intensively. Nowadays it is obvious that myeloid cells, especially DCs, are crucial for the adaptive and innate immune response against intracellular pathogens such as Leishmania major parasites. Based on the overlapping expression of molecules that were commonly used to classify myeloid cells, it becomes difficult to denominate those cell types precisely. Of note, most of these markers used for myeloid cell identification are expressed on a broad range of myeloid cells, and should therefore be handled with care if used for subtyping of myeloid cells. In this mini-review we aim to discuss the relative impact of DCs that release TNF and nitric oxide (Tip-DCs) and myeloid cells with suppressive capacities (myeloid-derived suppressor cells, MDSCs) in infectious diseases such as experimental leishmaniasis. In our point of view it cannot be excluded that the novel subsets that were denominated as "Tip-DCs" and "MDSCs" might not be classical "subsets" but rather represent myeloid cells in a transient maturation stage expressing different genes, in response to the surrounding environment.
